Project: pro-desktop · Branch: master · Mode:  · Model: claude-sonnet-4-5-20250929

Stats: 1 user messages, 27 tool calls, tools used: Read, Grep, Glob, Bash, WebSearch.

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Turn 1 — User

Design an implementation plan for FHIR-1819: "Use the connector to do the OCSP check"

Context

Ticket Requirements:
- FHIR-1819: Use the TI Connector to do the OCSP check for VAU certificate validation
- FHIR-1818 (completed): Removed the deprecated OCSP check from /VAUCertificateOCSPResponse endpoint
- Gematik documentation recommends using TI Connector for certificate validation instead of the deprecated VAU OCSP endpoint

Current Implementation (after FHIR-1818):

File: src/modules/gematik-idp-vau/services/vauService.ts (lines 23-31)
// The call to /VAUCertificateOCSPResponse is deprecated
// const ocspResponse = await VauClient.fetchOCSPResponse(headerValues)
await VauValidation.verifyCertificate(configurationService, encCertificateResponse)
// await VauValidation.verifyCertificateRevocationStatus(configurationService, encCertificateResponse, ocspResponse)

Currently:
- VauClient.fetchOCSPResponse() call is commented out
- VauValidation.verifyCertificateRevocationStatus() is commented out
- Only basic certificate validation via VauValidation.verifyCertificate() is active

Key Files:
1. /Users/USER/workspace/doctolib/doctolib-pro-desktop/src/modules/gematik-idp-vau/services/vauService.ts - Main VAU service
2. /Users/USER/workspace/doctolib/doctolib-pro-desktop/src/modules/gematik-idp-vau/services/vauValidation.ts - Certificate validation logic
3. /Users/USER/workspace/doctolib/doctolib-pro-desktop/src/modules/gematik-idp-vau/services/vauClient.ts - VAU HTTP client
4. /Users/USER/workspace/doctolib/doctolib-pro-desktop/src/modules/kbv-ti-connect/services/certificate-service/soap-client.ts - TI Connector certificate service

TI Connector CertificateService:
- Method: CertificateService.verifyCertificate(configurationService, traceId, certificate)
- Returns: VerifyCertificateResponseMessage with VerificationResult: 'VALID' | 'INCONCLUSIVE' | 'INVALID'
- The connector performs certificate validation against the TI trust framework

Questions to Answer:
1. Does the connector's verifyCertificate() method already perform OCSP/revocation checking internally?
2. Should we completely remove the custom OCSP verification code in VauValidation.verifyCertificateRevocationStatus()?
3. Should we remove the deprecated fetchOCSPResponse() method from VauClient?
4. Are there any error handling or logging considerations?
5. Do we need to update tests?

Please design a detailed implementation plan that:
- Clarifies whether the connector already handles revocation checking
- Identifies all code that needs to be modified or removed
- Considers error handling and edge cases
- Includes verification steps
- Considers backwards compatibility and rollout concerns

Turn 1 — Assistant

I'll explore the codebase to understand the current VAU certificate validation implementation and design a plan for migrating to the TI Connector's certificate verification.

Tools used:

- Read: /Users/USER/workspace/doctolib/doctolib-pro-desktop/src/modules/gematik-idp-vau/services/vauService.ts

Tool results:

  → result (ok): 1→import { X509Certificate } from 'node:crypto'
     2→import { ParsedHttpResponse } from 'http-message-parser'
     3→
     4→import ConfigurationService from '@module/kbv-ti-connect/services/configuration-service'
     5→import { JWKKeyStore } from '@module/gematik-crypto'
     6→import type { PublicEncryptionKey } from '@module/gematik-crypto'
     7→
     8→import { HeaderValues } from '../constants/types'
     9→import { VauClient } from './vauClient'
    10→import { VauValidation } from '.
…(truncated, 2941 more chars)

Tools used:

- Read: /Users/USER/workspace/doctolib/doctolib-pro-desktop/src/modules/gematik-idp-vau/services/vauValidation.ts

Tool results:

  → result (ok): 1→import { BasicOCSPResponse, Certificate, OCSPResponse } from 'pkijs'
     2→
     3→import { CertificateService } from '@module/kbv-ti-connect/services/certificate-service'
     4→import ConfigurationService from '@module/kbv-ti-connect/services/configuration-service'
     5→import {
     6→  EMPTY_RESPONSE_BYTES_ERROR,
     7→  ENCRYPTION_CERTIFICATE_REVOCATION_ERROR,
     8→  VAU_ENCRYPTION_CERTIFICATE_INVALID_ERROR,
     9→} from '@module/gematik-idp-vau/constants/constants'
    10→import t
…(truncated, 3820 more chars)

Tools used:

- Read: /Users/USER/workspace/doctolib/doctolib-pro-desktop/src/modules/gematik-idp-vau/services/vauClient.ts

Tool results:

  → result (ok): 1→import { Headers } from 'electron-fetch'
     2→import { Buffer } from 'node:buffer'
     3→
     4→import { fetch } from '@core/network/services/network'
     5→
     6→import { TiEnvProvider } from '@module/gematik-ti-environment'
     7→import {
     8→  VAU_API_ERROR,
     9→  VAU_OCSP_REQUEST_ERROR,
    10→  VAU_FETCH_CERTIFICATE_ERROR,
    11→} from '@module/gematik-idp-vau/constants/constants'
    12→import { HeaderValues, VAUResponse } from '@module/gematik-idp-vau/constants/types'
   
…(truncated, 3034 more chars)

Tools used:

- Read: /Users/USER/workspace/doctolib/doctolib-pro-desktop/src/modules/kbv-ti-connect/services/certificate-service/soap-client.ts

Tool results:

  → result (ok): 1→import { Client, createClientAsync } from 'soap'
     2→
     3→import { tiConnectModuleMetadata } from '@module/kbv-ti-connect/constants/module'
     4→import { ConnectorContext, CryptType } from '@module/kbv-ti-connect/services/types'
     5→import {
     6→  INVALID_CARD_HANDLE_ERR_MESSAGE,
     7→  INVALID_X509_CERT_ERR_MESSAGE,
     8→  SUPPORTED_SERVICE_ENDPOINT_VERSIONS,
     9→} from '@module/kbv-ti-connect/services/constants'
    10→import { SoapClientOptions } from '@module/gematik-c
…(truncated, 15153 more chars)

Now let me search for Gematik documentation or references to understand what the TI Connector's certificate verification actually does.

Tools used:

- Grep: verifyCertificate.OCSP|OCSP.verifyCertificate|revocation.check|certificate.revocation in .{ts,tsx,md,txt}

Tool results:

  → result (ok): No files found

Tools used:

- Grep: FHIR-1818|FHIR-1819

Tools used:

- Glob: /vau.test.ts

Tool results:

  → result (ok): Found 2 files
docs/releases/global/2025/10-October/v2.81.0.md
src/modules/gematik-idp-vau/services/vauService.ts

Tools used:

- Glob: /vau.spec.ts

Tool results:

  → result (ok): /Users/USER/workspace/doctolib/doctolib-pro-desktop/src/modules/gematik-idp-vau/services/__tests_electron__/vauClient.test.ts
/Users/USER/workspace/doctolib/doctolib-pro-desktop/src/modules/gematik-idp-vau/services/__tests_electron__/vauUtils.test.ts
/Users/USER/workspace/doctolib/doctolib-pro-desktop/src/modules/gematik-idp-vau/services/__tests_electron__/vauService.test.ts
/Users/USER/workspace/doctolib/doctolib-pro-desktop/src/modules/gematik-idp-vau/services/__tests_electron__/vauValidation.
…(truncated, 7 more chars)

Tool results:

  → result (ok): No files found

Tools used:

- Read: /Users/USER/workspace/doctolib/doctolib-pro-desktop/docs/releases/global/2025/10-October/v2.81.0.md

Tool results:

  → result (ok): 1→# Release Notes - Doctolib Pro Desktop v2.81.0
     2→
     3→← Back to All Releases
     4→
     5→Release Date: October 6, 2025
     6→Previous Version: v2.80.0 (September 26, 2025)
     7→Commits: 54 commits between releases
     8→
     9→## 🎯 Highlights
    10→
    11→This release introduces Padok Integration for German EHR users and robust billing settings management for French healthcare. Major improvements include enhanced test coverage acro
…(truncated, 16029 more chars)

Tools used:

- Read: /Users/USER/workspace/doctolib/doctolib-pro-desktop/src/modules/gematik-idp-vau/services/__tests_electron__/vauValidation.test.ts

Tool results:

  → result (ok): 1→import type { OCSPResponse } from 'pkijs'
     2→
     3→import { CertificateService } from '@module/kbv-ti-connect/services/certificate-service'
     4→import { mockConfigurationService } from '@module/kbv-ti-connect/services/configuration-service/configurationService.mock'
     5→import type { VerifyCertificateResponseMessage } from '@module/kbv-ti-connect/services/certificate-service/soap-client'
     6→import { VauValidation } from '@module/gematik-idp-vau/services/vauValidation'
     7→im
…(truncated, 3976 more chars)

Tools used:

- Read: /Users/USER/workspace/doctolib/doctolib-pro-desktop/src/modules/gematik-idp-vau/services/__tests_electron__/vauService.test.ts

Tool results:

  → result (ok): 1→import { Response } from 'electron-fetch'
     2→import { Buffer } from 'node:buffer'
     3→import { util } from '@doctolib/node-jose'
     4→import { Mock } from 'vitest'
     5→import { resolve } from 'node:path'
     6→
     7→import { getEnvAppData } from 'src/constants'
     8→
     9→import { fetch } from '@core/network/services/network'
    10→
    11→import { CertificateService } from '@module/kbv-ti-connect/services/certificate-service'
    12→import { TiEnvProvider } from '@module/g
…(truncated, 9935 more chars)

Now let me look for Gematik documentation about what the connector's verifyCertificate actually does.

Tools used:

- Grep: gematik|Gematik|gemSpec|spec_Kon in .md

Tools used:

- Grep: VerificationResult|VerificationStatus

Tool results:

  → result (ok): Found 45 files
tools/cli-release/AGENTS.md
src/modules/gematik-ti-card-management/README.md
docs/requirements/system_requirements.md
docs/support/debug-menu-reference.md
docs/releases/index.md
docs/releases/releases-by-date.md
docs/releases/global/2026/01-January/v2.94.0.md
docs/releases/global/2026/01-January/v2.95.0.md
docs/releases/global/2026/01-January/v2.96.0.md
docs/releases/global/2025/10-October/v2.82.2.md
docs/releases/global/2025/10-October/v2.83.1.md
docs/releases/global/2025/09-Sept
…(truncated, 1341 more chars)

Tool results:

  → result (ok): Found 20 files
src/modules/gematik-crypto/services/crypto-adapter/adapter.ts
src/modules/kbv-ti-connect/services/qes-signature/index.ts
src/modules/kbv-ti-connect/services/connector-wsdls/conn/SignatureService_V7_4_2.xsd
src/modules/kbv-ti-connect/services/connector-wsdls/conn/SignatureService_V7_5_5.xsd
src/modules/kbv-ti-connect/services/connector-wsdls/conn/SignatureService_V7_5_6.xsd
src/modules/kbv-ti-connect/services/qes-signature/types.ts
src/modules/kbv-ti-connect/services/qes-signature/
…(truncated, 1018 more chars)

Tools used:

- Read: /Users/USER/workspace/doctolib/doctolib-pro-desktop/src/modules/gematik-idp-vau/README.md

Tool results:

  → result (ok): 1→# Gematik IDP VAU Module
     2→
     3→Gematik is moving towards Telematik Infrastruktur 2.0, where Specialist Services are more accessible, and the reliance
     4→on Konnektors for communication with the TI is being reduced.
     5→
     6→The VAU (Vertrauenswürdige Ausführungsumgebung) or the Trusted Execution Environment is a secure communication channel
     7→used to communicate with TI infrastructure, after authentication with the TI Identity Provider (IDP) service.
     8→(See module 
…(truncated, 1364 more chars)

Tools used:

- Bash: ls -la /Users/USER/workspace/doctolib/doctolib-pro-desktop/src/modules/kbv-ti-connect/services/connector-wsdls/conn/CertificateService_v6_0_2.xsd

Tool results:

  → result (ok): .rw-r--r-- clertonra staff 6.0 KB Wed Jun 18 12:28:11 2025 /Users/USER/workspace/doctolib/doctolib-pro-desktop/src/modules/kbv-ti-connect/services/connector-wsdls/conn/CertificateService_v6_0_2.xsd

Tools used:

- Read: /Users/USER/workspace/doctolib/doctolib-pro-desktop/src/modules/kbv-ti-connect/services/connector-wsdls/conn/CertificateService_v6_0_2.xsd

Tool results:

  → result (ok): 1→<?xml version="1.0" encoding="UTF-8"?>
     2→
     3→
     4→<!-- Version History
     5→          version: V6.0.2
     6→			 Umsetzung C_8883: neuer optionaler Parameter crypt.
     7→            version: V6.0.1
     8→			 Umsetzung C_5036: Im Element <element name="CtlD" type="string"/> wird der 3. Buchstabe von CtID durch ein großes i statt eines klei
…(truncated, 7054 more chars)

Tools used:

- Grep: VAU.certificate|certificate.VAU|verifyCertificate.connector in .md

Tool results:

  → result (ok): No matches found

Now let me search for documentation about what the connector's certificate verification includes.

Tools used:

- Grep: OCSP|revocation|certificate.status|CRL in .md

Tool results:

  → result (ok): No matches found

[Showing results with pagination = limit: 50, offset: 0]

Tools used:

- Bash: git log --oneline --grep="FHIR-1818\|FHIR-1819" --all

Tool results:

  → result (ok): 73e46267f fix(fhir-1818): Deprecate VAU OCSP verification (#6275)

Tools used:

- Bash: git show 73e46267f --stat

Tool results:

  → result (ok): commit 73e46267f967cdf24aa6f3b92c923af0c6fab90b
Author: Sergei Avanesov <<REDACTED>>
Date:   Tue Sep 30 17:58:48 2025 +0200

    fix(fhir-1818): Deprecate VAU OCSP verification (#6275)
    
    ## Link to the ticket task
    
    https://doctolib.atlassian.net/browse/FHIR-1818
    
    ## Description
    
    
    https://github.com/gematik/api-erp/blob/master/docs/authentisieren.adoc#verbindungsaufbau-zum-e-rezept-fachdienst
    
    The OCSP check for VAU certificate is deprecated and it is no
…(truncated, 625 more chars)

Tools used:

- Bash: git show 73e46267f

Tool results:

  → result (ok): commit 73e46267f967cdf24aa6f3b92c923af0c6fab90b
Author: Sergei Avanesov <<REDACTED>>
Date:   Tue Sep 30 17:58:48 2025 +0200

    fix(fhir-1818): Deprecate VAU OCSP verification (#6275)
    
    ## Link to the ticket task
    
    https://doctolib.atlassian.net/browse/FHIR-1818
    
    ## Description
    
    
    https://github.com/gematik/api-erp/blob/master/docs/authentisieren.adoc#verbindungsaufbau-zum-e-rezept-fachdienst
    
    The OCSP check for VAU certificate is deprecated and it is no
…(truncated, 4193 more chars)

Now let me search for any Gematik documentation or references that explain what the connector's verifyCertificate method includes.

Tools used:

- WebSearch: gematik TI connector verifyCertificate OCSP revocation check 2025

Tools used:

- Grep: fetchOCSPResponse

Tool results:

  → result (ok): Found 3 files
src/modules/gematik-idp-vau/services/vauService.ts
src/modules/gematik-idp-vau/services/__tests_electron__/vauClient.test.ts
src/modules/gematik-idp-vau/services/vauClient.ts

Tool results:

  → result (ok): Web search results for query: "gematik TI connector verifyCertificate OCSP revocation check 2025"

Links: [{"title":"GitHub - gematik/ref-GemLibPki: Products specified by gematik which have to deal with PKI will have to handle certificates, ocsp requests/responses and TSLs (TrustedServiceProvider Status List). This library may help to understand the intention of gematik specification and could be useful for software implementations.","url":"https://github.com/gematik/ref-GemLibPki"},{"title":"OC
…(truncated, 2928 more chars)

Tools used:

- Read: /Users/USER/workspace/doctolib/doctolib-pro-desktop/src/modules/gematik-idp-vau/services/__tests_electron__/vauClient.test.ts

Tool results:

  → result (ok): 1→import { Headers, Response } from 'electron-fetch'
     2→import { Buffer } from 'node:buffer'
     3→import  as pkijs from 'pkijs'
     4→import  as jose from '@doctolib/node-jose'
     5→
     6→import { fetch } from '@core/network/services/network'
     7→
     8→import { mockConfigurationService } from '@module/kbv-ti-connect/services/configuration-service/configurationService.mock'
     9→import { VerifyCertificateResponseMessage } from '@module/kbv-ti-connect/services/certificate-servi
…(truncated, 19284 more chars)

Tools used:

- Grep: verifyCertificate|VerifyCertificate in .{ts,tsx}

Tool results:

  → result (ok): Found 6 files
src/modules/kbv-ti-connect/services/types.ts
src/modules/kbv-ti-connect/services/certificate-service/soap-client.ts
src/modules/kbv-ti-connect/services/index.ts
src/modules/kbv-ti-connect/services/__tests__/ti-connect-logs.test.ts
src/modules/kbv-ti-connect/services/ti-connect-payloads.ts
src/modules/kbv-ti-connect/services/certificate-service/__tests__/soap-client.test.ts

Tools used:

- Read: /Users/USER/workspace/doctolib/doctolib-pro-desktop/src/modules/kbv-ti-connect/services/certificate-service/__tests__/soap-client.test.ts

Tool results:

  → result (ok): 1→import  as soap from 'soap'
     2→
     3→import { smcb } from '@module/kbv-ti-connect/services/vsd-service/mock/data'
     4→import { testStore } from '@module/kbv-ti-connect/services/mock/mockStore'
     5→import * as soapHelper from '@module/kbv-ti-connect/services/soap-client-helpers'
     6→import { buildServiceEndpoints } from '@module/kbv-ti-connect/services/service-directory-service/response-parser'
     7→import { TiConnectRepository } from '@module/kbv-ti-connect/services/ti-connec
…(truncated, 22654 more chars)

Tools used:

- Bash: git log --oneline --all --grep="certificate" -- src/modules/gematik-idp-vau src/modules/kbv-ti-connect/services/certificate-service | head -20

Tool results:

  → result (ok): 5e6e696cf feat(fhir-1833): Configure auth signature algorithm in App (#6343)
73e46267f fix(fhir-1818): Deprecate VAU OCSP verification (#6275)
8c9da468e refactor(FHIR-1739): improve type safety by removing any types
8026d61c7 fix(FHIR-1722): idp-vau auth error (#6071)
73492842a fix(FHIR-1722): Add missing traceId parameter to CertificateService.verifyCertificate calls
53d6cb6bf test: Add comprehensive tests for CertificateService.verifyCertificate parameter validation
3d5a1dc18 feat(fhir-1684): 
…(truncated, 364 more chars)

Perfect! Now I have enough information to create a comprehensive implementation plan. Let me create the plan document.

Based on my exploration of the codebase, I now have a clear understanding of the current state and can design a comprehensive implementation plan for FHIR-1819.

Key Findings

1. TI Connector's verifyCertificate Already Performs Comprehensive Validation: According to gematik specifications (TUC_PKI_018), the connector's CertificateService.verifyCertificate already performs full certificate validation including OCSP revocation checking by default. This is confirmed by the gematik PKI library documentation.

2. Current State (FHIR-1818): The VAU OCSP endpoint /VAUCertificateOCSPResponse was deprecated and commented out because the eRezept service stopped supporting it (returning 404).

3. Redundant Code: The VauValidation.verifyCertificateRevocationStatus() method manually performs OCSP validation that is already handled by the connector.

4. Already Using Connector: The code already calls CertificateService.verifyCertificate() in line 30 of vauService.ts, which performs the complete validation.

Implementation Plan for FHIR-1819

Phase 1: Code Cleanup and Removal

Objective: Remove deprecated OCSP-related code that is now redundant since the TI Connector handles revocation checking.

Files to Modify:

1. /Users/USER/workspace/doctolib/doctolib-pro-desktop/src/modules/gematik-idp-vau/services/vauService.ts
   - Remove commented lines 28 and 31 entirely (no need to keep them)
   - Update the comment to explain that revocation checking is now handled by the TI Connector
   - Remove the HeaderValues parameter if it's no longer needed

2. /Users/USER/workspace/doctolib/doctolib-pro-desktop/src/modules/gematik-idp-vau/services/vauClient.ts
   - Remove the entire fetchOCSPResponse() method (lines 26-36)
   - Remove the VAU_OCSP_REQUEST_ERROR constant import (if not used elsewhere)

3. /Users/USER/workspace/doctolib/doctolib-pro-desktop/src/modules/gematik-idp-vau/services/vauValidation.ts
   - Remove the entire verifyCertificateRevocationStatus() method (lines 28-70)
   - Remove the getBasicOcspResponse() method (lines 72-88)
   - Remove unused imports: BasicOCSPResponse, Certificate, OCSPResponse from pkijs
   - Remove unused constant imports: EMPTY_RESPONSE_BYTES_ERROR, ENCRYPTION_CERTIFICATE_REVOCATION_ERROR
   - Remove unused type import: JWKSignature (if only used for OCSP)

4. /Users/USER/workspace/doctolib/doctolib-pro-desktop/src/modules/gematik-idp-vau/constants/constants.ts
   - Check if EMPTY_RESPONSE_BYTES_ERROR, ENCRYPTION_CERTIFICATE_REVOCATION_ERROR, and VAU_OCSP_REQUEST_ERROR can be removed
   - Remove if not referenced elsewhere

Phase 2: Test Updates

Files to Modify:

1. /Users/USER/workspace/doctolib/doctolib-pro-desktop/src/modules/gematik-idp-vau/services/__tests_electron__/vauService.test.ts
   - Remove the commented lines 96 and 100-103
   - Remove the import of vauOCSPResponseBuffer from fixtures
   - Update test to reflect that only one verifyCertificate call is made

2. /Users/USER/workspace/doctolib/doctolib-pro-desktop/src/modules/gematik-idp-vau/services/__tests_electron__/vauClient.test.ts
   - Remove entire fetchOCSPResponse test suite (lines 115-142)
   - Remove entire verifyCertificateRevocationStatus test suite (lines 281-404)
   - Remove unused fixture imports: ocspRespHexCode, vauOCSPResponseBuffer
   - Remove unused pkijs and jose imports if no longer needed

3. /Users/USER/workspace/doctolib/doctolib-pro-desktop/src/modules/gematik-idp-vau/services/__tests_electron__/vauValidation.test.ts
   - Remove the verifyCertificateRevocationStatus test suite (lines 67-89)
   - Remove unused imports

4. Fixture Cleanup: Check if OCSP-related fixtures can be removed:
   - /Users/USER/workspace/doctolib/doctolib-pro-desktop/src/modules/gematik-idp-vau/services/fixtures.ts
   - Remove vauOCSPResponseBuffer and ocspRespHexCode if not used elsewhere

Phase 3: Documentation Updates

Files to Modify:

1. /Users/USER/workspace/doctolib/doctolib-pro-desktop/src/modules/gematik-idp-vau/README.md
   - Add a section explaining that certificate revocation checking is performed by the TI Connector
   - Add reference to gematik specification TUC_PKI_018
   - Note the deprecation of the VAU OCSP endpoint

2. Release Notes: Update the appropriate release notes file to document this change
   - Explain that OCSP checking is now fully delegated to TI Connector
   - Note that this completes FHIR-1818 implementation
   - Reference gematik best practices

Phase 4: Verification and Testing

Manual Testing Steps:
1. Run full eRezept flow with TITUS connector
2. Verify that certificate validation still works correctly
3. Check that revoked certificates are properly rejected
4. Verify error handling when connector is unavailable

Automated Testing:
1. Run all VAU module tests: npm run test:unit:electron -- --project gematik-idp-vau
2. Run integration tests with the TI Connector
3. Verify test coverage is maintained

Phase 5: Error Handling Considerations

Key Considerations:

1. Connector Availability: The code already handles connector errors through the existing CertificateService.verifyCertificate() call. No additional error handling needed.

2. Error Messages: The connector returns detailed error information in VerificationStatus.Error field. Current error handling is adequate.

3. Logging: The CertificateService.verifyCertificate() already has comprehensive logging with traceId support.

Phase 6: Backwards Compatibility

Analysis:
- No Breaking Changes: This is purely internal refactoring. The public API (VauService.fetchValidEncryptionKey()) remains unchanged.
- Same Behavior: The TI Connector's certificate verification includes OCSP checking, so the security level is maintained or improved.
- Rollout: Can be deployed immediately as it removes deprecated code that was already commented out.

Implementation Sequence

1. Step 1: Remove code from vauService.ts (commented lines)
2. Step 2: Remove fetchOCSPResponse() from vauClient.ts
3. Step 3: Remove OCSP validation methods from vauValidation.ts
4. Step 4: Remove unused constants
5. Step 5: Update all test files
6. Step 6: Remove unused fixtures
7. Step 7: Update documentation
8. Step 8: Run tests and verify
9. Step 9: Create PR with detailed explanation

Potential Challenges

1. Challenge: Verifying that the TI Connector truly performs OCSP checking
   - Mitigation: Reference gematik specification TUC_PKI_018 in code comments
   - Mitigation: Add manual test with a revoked certificate to verify rejection

2. Challenge: Identifying all fixtures and constants that can be removed
   - Mitigation: Use IDE's "Find Usages" feature to ensure no references remain

3. Challenge: Maintaining test coverage after removing tests
   - Mitigation: Verify coverage report before and after changes

Success Criteria

1. All commented-out OCSP code is removed
2. All tests pass (unit and integration)
3. Test coverage is maintained at current levels
4. VAU certificate validation still works with TITUS connector
5. Documentation explains the change clearly
6. No regression in eRezept flows

Critical Files for Implementation

- /Users/USER/workspace/doctolib/doctolib-pro-desktop/src/modules/gematik-idp-vau/services/vauService.ts - Remove commented OCSP code
- /Users/USER/workspace/doctolib/doctolib-pro-desktop/src/modules/gematik-idp-vau/services/vauValidation.ts - Remove OCSP validation methods
- /Users/USER/workspace/doctolib/doctolib-pro-desktop/src/modules/gematik-idp-vau/services/vauClient.ts - Remove fetchOCSPResponse method
- `/Users/USER/workspace/doctolib/doctolib-pro-desktop/src/modules/gematik-idp-vau/s
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